tile: convert uses of "inv" to "finv"

The "inv" (invalidate) instruction is generally less safe than "finv"
(flush and invalidate), as it will drop dirty data from the cache.
It turns out we have almost no need for "inv" (other than for the
older 32-bit architecture in some limited cases), so convert to
"finv" where possible and delete the extra "inv" infrastructure.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

3 files changed, 22 insertions, 57 deletions

diff --git a/arch/tile/include/asm/cacheflush.h b/arch/tile/include/asm/cacheflush.h
index 0fc63c4..92ee4c8 100644
--- a/arch/tile/include/asm/cacheflush.h
+++ b/arch/tile/include/asm/cacheflush.h
@@ -75,23 +75,6 @@ static inline void copy_to_user_page(struct vm_area_struct *vma,
 #define copy_from_user_page(vma, page, vaddr, dst, src, len) \
 	memcpy((dst), (src), (len))
 
-/*
- * Invalidate a VA range; pads to L2 cacheline boundaries.
- *
- * Note that on TILE64, __inv_buffer() actually flushes modified
- * cache lines in addition to invalidating them, i.e., it's the
- * same as __finv_buffer().
- */
-static inline void __inv_buffer(void *buffer, size_t size)
-{
-	char *next = (char *)((long)buffer & -L2_CACHE_BYTES);
-	char *finish = (char *)L2_CACHE_ALIGN((long)buffer + size);
-	while (next < finish) {
-		__insn_inv(next);
-		next += CHIP_INV_STRIDE();
-	}
-}
-
 /* Flush a VA range; pads to L2 cacheline boundaries. */
 static inline void __flush_buffer(void *buffer, size_t size)
 {
@@ -115,13 +98,6 @@ static inline void __finv_buffer(void *buffer, size_t size)
 }
 
 
-/* Invalidate a VA range and wait for it to be complete. */
-static inline void inv_buffer(void *buffer, size_t size)
-{
-	__inv_buffer(buffer, size);
-	mb();
-}
-
 /*
  * Flush a locally-homecached VA range and wait for the evicted
  * cachelines to hit memory.
@@ -142,6 +118,26 @@ static inline void finv_buffer_local(void *buffer, size_t size)
 	mb_incoherent();
 }
 
+#ifdef __tilepro__
+/* Invalidate a VA range; pads to L2 cacheline boundaries. */
+static inline void __inv_buffer(void *buffer, size_t size)
+{
+	char *next = (char *)((long)buffer & -L2_CACHE_BYTES);
+	char *finish = (char *)L2_CACHE_ALIGN((long)buffer + size);
+	while (next < finish) {
+		__insn_inv(next);
+		next += CHIP_INV_STRIDE();
+	}
+}
+
+/* Invalidate a VA range and wait for it to be complete. */
+static inline void inv_buffer(void *buffer, size_t size)
+{
+	__inv_buffer(buffer, size);
+	mb();
+}
+#endif
+
 /*
  * Flush and invalidate a VA range that is homed remotely, waiting
  * until the memory controller holds the flushed values.  If "hfh" is
diff --git a/arch/tile/include/asm/uaccess.h b/arch/tile/include/asm/uaccess.h
index e4d44bd..f68503f 100644
--- a/arch/tile/include/asm/uaccess.h
+++ b/arch/tile/include/asm/uaccess.h
@@ -567,37 +567,6 @@ static inline unsigned long __must_check flush_user(
 }
 
 /**
- * inv_user: - Invalidate a block of memory in user space from cache.
- * @mem:   Destination address, in user space.
- * @len:   Number of bytes to invalidate.
- *
- * Returns number of bytes that could not be invalidated.
- * On success, this will be zero.
- *
- * Note that on Tile64, the "inv" operation is in fact a
- * "flush and invalidate", so cache write-backs will occur prior
- * to the cache being marked invalid.
- */
-extern unsigned long inv_user_asm(void __user *mem, unsigned long len);
-static inline unsigned long __must_check __inv_user(
-	void __user *mem, unsigned long len)
-{
-	int retval;
-
-	might_fault();
-	retval = inv_user_asm(mem, len);
-	mb_incoherent();
-	return retval;
-}
-static inline unsigned long __must_check inv_user(
-	void __user *mem, unsigned long len)
-{
-	if (access_ok(VERIFY_WRITE, mem, len))
-		return __inv_user(mem, len);
-	return len;
-}
-
-/**
  * finv_user: - Flush-inval a block of memory in user space from cache.
  * @mem:   Destination address, in user space.
  * @len:   Number of bytes to invalidate.
diff --git a/arch/tile/include/uapi/asm/cachectl.h b/arch/tile/include/uapi/asm/cachectl.h
index af4c9f9..572ddca 100644
--- a/arch/tile/include/uapi/asm/cachectl.h
+++ b/arch/tile/include/uapi/asm/cachectl.h
@@ -29,8 +29,8 @@
  * to honor the arguments at some point.)
  *
  * Flush and invalidation of memory can normally be performed with the
- * __insn_flush(), __insn_inv(), and __insn_finv() instructions from
- * userspace.  The DCACHE option to the system call allows userspace
+ * __insn_flush() and __insn_finv() instructions from userspace.
+ * The DCACHE option to the system call allows userspace
  * to flush the entire L1+L2 data cache from the core.  In this case,
  * the address and length arguments are not used.  The DCACHE flush is
  * restricted to the current core, not all cores in the address space.